1. Field of the Invention
This invention relates to an apparatus for severing a web at a reversing winder, comprising a cutter bar provided with a cutter blade and pressure-applying means which are engageable with a core tube currently in the winder.
2. Description of Prior Art
Reversing winders are provided, as a rule, with two core tubes, one of which is in a winding position at a time. When a complete coil has been wound, the core tube on which the web has been wound is pivotally moved from the winding position to a delivery position and an empty core tube is moved to the winding position at the same time. The web remains connected to the coil during the pivotal movement of the empty and coil-carrying core tubes. Only when the coil-carrying core tube has been moved to the delivery position and the empty core tube has been moved to the winding position is the web severed by means of a cutter blade and the leading end of the incoming web connected to the empty core tube so that a new coil can be wound on the empty tube.
U.S. Pat. No. 2,942,796 discloses an apparatus which is of the kind described first hereinbefore and in which the operations by which the web is severed by means of a cutter blade and the leading end of the incoming web is connected to the still empty core tube, which has been moved to the winding position, are performed at the same time. For the connection to the leading end of the incoming web, the empty core tube is provided with an adhesive tape, at which the leading end of the incoming web is forced against the core tube by means of a sheet metal element which is disposed closely below the cutter blade. For this purpose, the pressure-applying plate is pivotally moved in unison with the cutter blade and severs the web closely beside the empty core tube which has been pivotally moved to the winding position.
Such an apparatus will operate satisfactorily if core tubes are used which have a uniform diameter. On the other hand, if core tubes are used which are larger in diameter than other core tubes, the cutter blade will strike against the core tube as the cutter blade arrives in the severing position. For this reason , this known apparatus cannot be used with core tubes which differ in diameter.